Survey : CLIO/10/1979 (part of CEFAS Historic surveys)

This survey was undertaken by Cefas as part of the CEFAS Historic surveys;

Station and biological data collected during research surveys carried out by
Cefas (formerly Directorate of Fisheries) in seas around the UK, mostly in the
North Sea, since 1902. The survey hauls are not laid out systematically as a
grid, as in current International Bottom Trawl Surveys (IBTS) and are widely
distributed over (especially) southern and central North Sea areas. Gears and
protocols were not standardised throughout, due to the long term nature of the
series. Surveys took place in each season. Data are lacking for the periods of
both World Wars. In some periods (e.g. the early 1900s), all species caught
were recorded, whereas in other periods (e.g. 1920s-30s), only the key
commercial species (e.g., Plaice, Sole and Cod) were recorded systematically.
Note that some surveys targeted particular species (notably Plaice).

Survey took place between 02/10/1979 and 14/10/1979 on Clione

Equipment used during this survey :

- Frame Trawl BoothBay Inverted 1 strop, 3 depressors, Fryma Net
- Otter Trawl 78ft Granton No bridles, liner, rubber bobbins

Survey operations were undertaken on 61 stations

74 different species were caught on this survey

本调查由Cefas（前身为渔业局）发起，作为其历史调查系列的一部分。自1902年以来，Cefas在环绕英国的海域，尤其是北海区域，进行了多次研究调查，并收集了相关站点和生物数据。与现行的国际底拖网调查（IBTS）不同，调查捕获物并非按网格系统系统地排列，而是广泛分布于北海的南部和中部地区。由于该系列数据的长期性，设备和协议并未实现标准化。调查在每个季节都会进行。两次世界大战期间的数据缺失。在某些时期（如20世纪初），记录了所有捕获的物种，而在其他时期（如1920年代至1930年代），仅系统地记录了关键的商业物种（例如，鳎鱼、鳎鱼和鳕鱼）。值得注意的是，某些调查专注于特定物种（尤其是鳎鱼）。在1979年10月2日至14日，对Clione进行的调查中，使用了以下设备：

- Frame Trawl BoothBay Inverted 1 firstrop，3 depressors，Fryma Net
- Otter Trawl 78ft Granton No bridles，liner，rubber bobbins

调查在61个站点进行，共捕获了74种不同的物种。